Perchlorate is one of the contaminants increasingly found in wastewater, groundwater, surface water and soil. Perchlorate is known for its adverse effects to human health by interfering with iodide uptake into the thyroid gland [1-2]. It is highly soluble in water and organic solvents, and is difficult to complex with common cations, organic or inorganic. Although several complexants of perchlorate were suggested for gravimetric analysis purposes, such as methylene blue, nitron, tetraphenyl-arsonium and cetyltrimethylammonium, no complexant has been identified as suitable for large-scale water treatment, mainly due to high toxicity and relatively high solubility, as well as the requirement for drastic pH manipulation in order to facilitate precipitation. The common treatment processes of water include absorption and/or ion exchange by active groups located on the surface of an adsorbing substrate [3-4]. However, the efficiency of these processes is limited, typically when perchlorate concentration are >10 ppm, as saturation of the active absorption sites is rapidly achieved, thereby preventing further perchlorate adsorption. In addition, the regeneration process of such substrates results in the formation of perchlorate-rich brines, which need to be further processed, rendering the process costly and environmentally problematic. Other processes include bacterial decomposition of perchlorate. Such processes are relatively slow and require constant monitoring and maintenance of strict conditions throughout the process [5-6].
Therefore, there is a need for an efficient and rapid process for the removal of perchlorate from relatively highly concentrated aqueous solutions of perchlorate.